1. Field of the Invention
The present invention relates to a planar integration of a free-space optical system, more particularly, to a method of integrating a crossover switching network having several optical elements such as mirrors, lenses, beam splitters etc. spatially on a single wafer with an acute angle prism array.
2. Background Art
In a conventional crossover network of an optical system, individual optical parts such as mirrors, lenses, beam splitters and prisms are spaced apart, as shown in FIG. 1(A). According to such an arrangement of the optical parts, the size of the optical system is be increased due to the spatial arrangement of the parts.
Furthermore, it is difficult to manufacture the optical parts in such as optical system with an alignment accuracy of equal to less than 1 .mu.m.
Also, once the optical system has been constructed, it is difficult to keep the system with the foregoing alignment.
An optical crossover interconnection capable of being used practically in a switching network requires a small sized optical system having an alignment accuracy of equal to or less than 1 .mu.m.